Hi thebigcheeze,

I use a multi platform app called MessySMS to encrypt my messages. It's very simple, basically you share a passphrase with your contacts and later use it to encrypt and decrypt your messages.
Messy interacts with your SMS program but can be used to encrypt any text. This is a good option if you wish to encrypt a message once in a while, it's not an option if you want to encrypt all outgoing messages.

Best wishes.
Banankolan

 

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